When I adopted two kittens from a shelter a couple of weeks ago — both as adorable as anything can possibly be, but with the relentless destructive energy of two tiny hurricanes — I didn’t realize that I was bucking a trend: America’s pet population is dropping, apparently (like so many things today) a casualty of our uncertain economy.According to a new survey by the American Veterinary Medical Association, the number of dogs kept as pets in the U.S. has fallen by 2 million since 2006, the last time the survey was done; the number of pet cats has fallen even more sharply, by 7.6 million. Americans aren’t abandoning the pets they already own; they’re just not as quick to adopt new pets when their old ones die.

Karen Felsted, the Texas vet who reported the results of the survey at the group’s annual meeting, says the problem is “clearly the economy,” according to USA Today.

Despite the drop in numbers, it’s clear that Americans still love pets. We collectively own 70 million dogs and 74 million cats. People are slightly more likely to own dogs than cats — 36.5% of American homes host at least one dog, while cats are in 30.4% of homes. But cat owners are more likely to own more than one.

But if Americans are growing more reluctant to take on the responsibilities of new pets, they may be doing themselves (much less the animals waiting in shelters to be adopted) a giant disservice and costing themselves more money than they save. Yes, pets cost money — the American Society for the Prevention of Cruelty to Animals, or the ASPCA, estimates that a medium-size dog will run you $695 a year in expenses, a cat only a little less at $670, and I think that’s lowballing it.

And all this can save you money. High blood pressure, for example, is not only bad for your health but also for your wallet, increasing your health care costs by more than $700 a year, according to one study — about as much as it costs to own a pet. Getting regular exercise — like the exercise you get from walking (or running) your dog — can cut your health costs by hundreds of dollars a year. And anything that reduces your risk of heart disease is a gigantic potential money saver — one study estimates the total lifetime cost of severe coronary artery disease, including both medical costs and the cost of lost productivity, can run a not-so-cool $1 million.

And pets can also be marvelous entertainment, as my kittens have shown over and over since I took them in. The sight of a tiny cat running full speed into a paper bag is always hilarious. And some of their acrobatics put America’s much celebrated Olympic gymnasts to shame.

Still, pet ownership isn’t for everyone. Some people are allergic; others just don’t like dogs or cats. Pets shed, they sometimes bite and have no moral qualms about destroying furniture or shoes. They also poop, which for some reason becomes your responsibility, not theirs. They require time and patience.

And pets can be a mixed bag for older people. While “pet therapy” offers nursing-home residents numerous health benefits, the hassles of owning a pet (from walking the dog to cleaning out the cat’s litter box) can mean more stress than stress relief for elderly owners. Even more worrying: having pets underfoot can contribute to falls, which can be debilitating and even deadly for many old people.

As for me, well, my first cat showed up on a friend’s doorstep one cold, wet night 14 years ago, barefoot and pregnant and desperately in need of food and attention. She was a handful — a scratcher and a biter and suspicious of everyone but me. But I loved her, and she loved me, in her way, and taking her in was one of the best decisions I ever made. She died this April after a long and (as far as I could tell) happy life. Now I’ve got two kittens tearing around (and tearing apart) the apartment. The fact that something as cute and ridiculous as a kitten can actually improve my health and save me money still strikes me as faintly amazing. What a bargain!